Bone Abstracts

Background: Low vitamin D concentrations among children and adolescents at northern latitudes are frequently observed. Also, inverse associations between 25-hydroxyvitamin D (25(OH)D) and PTH concentrations have been found in children of different ages. More studies on the link between vitamin D status and childhood bone health are needed.Objective: To evaluate the status of serum 25(OH)D in autumn and the association between 25(OH)D concentrations and b...

Osteoclast-poor autosomal recessive osteopetrosis is characterised by susceptibility to fracture despite high bone mineral density as a consequence of an absence of osteoclasts. One of the 12 receptor activator of NF-κB (RANK) mutations associated with this condition is a frameshift mutation encoding a protein that is truncated within the extracellular, N-terminal domain (R110Pfs). We investigated the effect of this mutation on osteoclast formation, receptor localisation ...

Background: Elevated plasma homocysteine levels are a risk factor for osteoporotic fractures. Supplementation with vitamin B12/folic acid lowers homocysteine levels. This study aimed to determine whether vitamin B12/folic acid supplementation reduces osteoporotic fracture incidence in hyperhomocysteinemic elderly.Methods: B-PROOF is a double-blind, randomized, placebo-controlled trial including 2 919 participants aged ≧65 years with elevated homocyste...

Introduction: Niemann–Pick disease (NPD) is a rare autosomal recessive lysosomal lipid storage disorder. It is caused by mutations of genes which products are involved in the metabolism of sphingolipids. Their dysfunction causes sphingomyelin to accumulate in different organs which leads to progressive multisystemic disorder. Types A and B NPD are caused by mutations in sphingomyelin phosphodiesterase-1 gene with deficiency of acid sphingomyelinase (ASM). Types C and D NP...

After trauma or carious lesion dental pulp healing is difficult to predict. In addition systemic diseases like diabetes mellitus can impair the regenerative capacity. New regenerative strategies target prolyl hydroxylase (PHD) by pharmacological inhibitors to stimulate hard and soft tissue healing. PHD inhibitors such as L-mimosine (L-MIM) induce vascular endothelial growth factor (VEGF) production by promoting angiogenesis. However, it is unclear if L-MIM is a feasible tool t...

We have reported femoral osteopenia in short term-vitamin D restricted rats without deterioration in tibial cortical bone volume (CBV), geometry or strength1. This study aimed to establish the effect of extended vitamin D deficiency in aged rat tibial volume and strength. Female Sprague-Dawley rats (9 m, n=6/group) were fed a diet containing varying vitamin D3 (D) levels (0, 2, 12, and 20 IU/day) with either low (0.1%, LCa) or high (1%, HCa) diet...

Biographical DetailsCraig B LangmanProfessor Craig B Langman, is the Isaac A Abt, MD, Professor of Kidney Diseases at the Feinberg School of Medicine, Northwestern University, Head of Kidney Diseases at the Ann and Robert H Lurie Children’s Hospital of Chicago. His research focuses on the basic and clinical expression of inherited or acquired d...

Osteoblasts have a high rate of energy consumption during bone formation and bone protein synthesis. Therefore, it is likely that decreased energy production that accompanies aging, could contribute to reduced osteoblast activity, a critical feature of senile osteoporosis, and that this reduction might be counteracted by favoring energy availability. Cells of the osteoblastic lineage generate 40–80% of the requested energy through fatty acid degradation, thus the modulati...

Paget’s disease of Bone (PDB) is caused by mutations in the gene encoding Sequestosome-1 (Q17STM1 or p62) that affect the C-terminal Ubiquitin-Associated (UBA) domain. A second isoform of Q17STM1 exists (referred to hereafter as 55kDa-Q17STM1), which lacks the N-terminal Phox and Bem1 (PB1) domain and has previously been reported to be ~45x more abundant than Q17STM1/p62 in osteoclasts. Mutations in the UBA domain will also occur in this isoform. Several of the UBA mutati...

Early-onset Paget’s disease of bone (ePDB), familial expansile osteolysis (FEO) and expansile skeletal hyperphosphatasia (ESH) are related syndromes caused by heterozygous tandem insertion duplication mutations within the signal peptide region of TNFRSF11a (encoding receptor activator of NFκB; RANK). Given that patients are always heterozygous for these mutations we have generated thirteen cell lines to investigate the molecular consequences of these mutations in...